1. Field of the Invention
This invention relates to an adjusting device for a lens mounting which enables the separation between optical elements and the fall of an optical member in a direction perpendicular to the optical axis to be adjusted.
2. Description of the Prior Art
As a conventional example, there is Japanese Laid-Open Patent Application No. SHO 56-77807 (entitled "Lens Separation Adjusting Device", in which an end surface of the axial length of one lens barrel is provided with a plurality of stair-like stepped portions, and an end surface of the axial length of another lens barrel is provided with a projected portion corresponding to the aforesaid stepped portion, so that when these two barrels are connected to each other, the aforesaid projected portion abuts on the one of the step surfaces of the aforesaid stepped portions which provides the required lens separation. Because the axial distance between the successive two of the stepped portions is relatively long, there is a drawback that infinitely fine spacing adjustment is impossible to carry out.
Also, after the spacing has been adjusted to the prescribed value, both barrels are fixedly secured to each other by set screws on the outer periphery thereof. Therefore, there is another drawback that the tightening on the outer periphery causes deformation of the barrel, giving a bad influence on the optical performance.